water problems driving me crazy?????

[PRTA79]

can't figure this one out
i have 2 32gal trash cans i make my rodi in , ones for salt , the other is for fresh only, their both identical, the ph of the fresh rodi is 9.2 ,when i mix the salt the ph drops to 8.0 hmmm? im using i/o salt but its not a bad batch cause i also tried tropic marin,and oceanic is there posibily some kind of chemical reaction happening here???

 

[clamm]

i had the a similar thing happen once when I installed a ro membrane in backwards, basically flushed it into my RO water...and killed my DI really quick. Do you have a tds meter that you can check the tds of the water in you ro/di bucket?

Otherwise, are you using a ph probe/meter to test it. I hear they aren't really accurate at really low TDS.

Have you compared your reading of the ro/di to a chemical based ph test?

Hope that gives you a few things to try.

You probably know, but to save a question "TDS" is total dissolved solids..

 

[PRTA79]

ph test

i have 2 ph meters on the tank
also tested with seatest kit both read same

 

[denvig]

http://www.bostonreefers.org/forums/showthread.php?p=159068#post159068

This thread will help

 

[PRTA79]

aeriating

tried that i ran a mag9 in the can with a venturi on it pulling fresh air in from outside!!!!! for a whole day with no results!!!

 

[wrassefan]

I thought that ph test kits for salt water and fresh water are different. You cannot get an accurate reading on your fresh rodi water using your saltwater test kit for ph....you would need to get a freshwater ph test kit....sounds like the fresh saltwater is testing out fine tho. My fresh IO saltwater tests out at 8...hth

 

[Jim Tansey]

I think wrassefan is correct on this, the salt water test kits and electronic meters/controllers are not designed for fresh water measurements.

Jim

 

[PRTA79]

fresh water test kit

ok just checked with test kit from koi pond it only reads up to 8.4 max
and it said 8.4

 

[denvig]

aeriating???

Read the whole thread
http://www.bostonreefers.org/forums/showthread.php?p=159068#post159068

 

[PRTA79]

am i missing something here??

ive tried both ways with the same results both times!
are you saying its normal for salt to have low ph?

 

[Pat H.]

can't figure this one out
i have 2 32gal trash cans i make my rodi in , ones for salt , the other is for fresh only, their both identical, the ph of the fresh rodi is 9.2 ,when i mix the salt the ph drops to 8.0 hmmm? im using i/o salt but its not a bad batch cause i also tried tropic marin,and oceanic is there posibily some kind of chemical reaction happening here???

I thought fresh water should have a pH around 7.0. I just checked my RO/DI water and I get around that with a fresh water pH kit I have lying around. 9.2 is really high. Not sure what the problem could be, but either your RO unit needs service or there was something in the barrel to contaminate like maybe kalk powder residue??

 

[PRTA79]

no kalk powder

the only thing i added was super buffer dkh awhile ago , that didnt work either
my di filter will need change soon but im only getting 5tds which isnt that bad

 

[PRTA79]

added chemicals

i wonder are there any chemicals the city might add to the water that would raise the ph ,but when mixed with salt react and cause it to drop

 

[wrassefan]

take some fresh rodi water and go to petco and have them test it with a freshwater ph kit....at least you will know...the fact that the saltwater comes out 8 on the saltwater test kit tells me that it should be fairly accurate using IO.

 

[PRTA79]

did that

ok just checked with test kit from koi pond it only reads up to 8.4 max
and it said 8.4

maxed it out

 

[wrassefan]

what is your straight tap water reading? got any distilled or bottled water to make sure your "koi test" is okay?

 

[PRTA79]

tap and poland spring

tap is same
poland spring 7.2 with test strip and 6.9 with probe

 

[PRTA79]

good idea btw

good idea checking the spring water ,but both test kit and probe are close
theres something screwy here ??

 

[wrassefan]

wonder if they are adding something into the water for high bacteria or some other water treatment?? I would call the town/city in the morning and ask

 

[PRTA79]

tap

fresh water quick dip test 8.4 higest it reads probe 9.1